The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Recently, there has been a growing interest on eco-friendly vehicles, such as a hybrid vehicle which runs on the power of an engine and a motor and an electric vehicle and a fuel cell vehicle which run on only the power of a motor.
Since the eco-friendly vehicle runs on only the power of the motor in a turn-off state of the engine that generates noise, or omits the engine, noise of travelling is hardly generated.
Meanwhile, when there is almost no traveling noise, a pedestrian at a surrounding of the vehicle may not recognize the approach of the vehicle, thus safety accidents may occur. In order to remove such limitations, the eco-friendly vehicles are using a virtual engine sound system (VESS) that allows pedestrians to easily recognize the presence and approach of a nearby vehicle by outputting virtual noise to the outside of the vehicle through a speaker.
A typical VESS generates noise through an electronic circuit and outputs the noise through an external speaker of the vehicle such that a nearby pedestrian or the like recognizes the presence of the vehicle.